The proposed work is directed toward gaining a further understanding of the normal growth and aging process of the lens. The study is focused on a correlation of morphological, biochemical, and physiological data that relates to the maintenance of lens transparency. The investigation includes a study of the cellular matrix (microtubules and microfibrils) in normal lenses and in cataracts, a study of the architectural changes in the capsule with age, a study of the ultrastructure of the developing of the human fetal lens, a study of the role of nutrition in development of the eye (rats on a low sodium diet and others on a protein deficient diet) with the possible development of a nuclear cataract model, a study of hypermature cataracts in relation to morphology and protein biochemistry, a study of the localization of intrinsic and extrinsic membrane polypeptides, and a participation in the Cooperative Cataract Research Group, directed toward the development of a universal cataract classification and data bank (based at Howe Laboratories, Harvard Medical School).